The invention relates in general to the field of integrated circuit packages and assemblies thereof, as well as methods of fabrication thereof. It is, in particular, directed to dense assembly, or stack, of overmolded, integrated circuit chip packages, where the packages of the stack are laterally soldered (e.g., edge soldered) to a transverse printed circuit board.
This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.
Printed circuit boards are routinely used to support and electrically connect various electronic components. PCBs use conductive tracks and contact pads, which are typically etched from a copper sheet laminated onto a non-conductive substrate (typically a FR-4 glass epoxy). PCBs can be single sided or double sided. One also knows multi-layer PCBs, which allow for higher component density.
With ever higher integration and higher speed of microprocessors and memory, more compact packaging assemblies are desired. High density interconnect boards have been proposed, which comprise blind and/or buried vias and offer higher circuitry density than traditional circuit boards. Beside, assemblies of PCBs have been proposed, allowing PCBs (with electronic components mounted thereon) to be placed close to each other in vertical stacks. More generally, PCBs may be packed in horizontal or vertical arrangements, using sockets to maintain and electrically connect them to, e.g., a base board.